Defibrillators are devices for providing life-saving electrical shock therapy to persons experiencing an irregular heart beat, such as Ventricular Fibrillation (VF). A defibrillator provides an electrical shock to the heart, in order to convert the irregular heart beat to a normal sinus rhythm. One type of defibrillator is surgically implanted in patients who are considered likely to need electrical shock therapy, precluding the necessity of constant monitoring by medical personnel.
A more commonly used type of defibrillator is the external defibrillator, which sends electrical shock pulses to the patient's heart through external electrodes applied to the patient's chest. External defibrillators may be manually operated, as are typically used in hospitals by medical personnel or may be semi-automatic, semi-automated, fully automatic, or fully automated devices, where they can be used in any location where an unanticipated need may occur.
Recent research has shown that administration of CPR therapy close to the time of the delivery of a defibrillation shock may be beneficial to a patient. Prior art defibrillator configurations have attempted to apply this finding by compressing the time gap between the analysis of the patient's ECG signal and the delivery of the defibrillation shock. However, these attempts have presented problems. For instance, one known defibrillator includes circuitry that reduces the charging time of the energy storage device. These types of defibrillators include complex circuitry, which can add more components to the defibrillator and increase the overall size of the apparatus. In certain instances, increase in size may not be favorable, especially because users of external defibrillators typically may need to travel from one site to another to administer treatment. Thus, a large, bulky machine may not be desirable. Moreover, the additional circuitry may be more costly to implement, and thereby may increase the price of the defibrillator.
Other defibrillators begin to charge the energy storage device as soon as power is turned on. However, a decision to shock is generally rendered in less than fifty percent (50%) of all cardiac arrest cases, and charging the energy storage device at every power on instance may reduce battery life. Yet other defibrillators allow caregivers to administer CPR therapy during the collection and analysis of the patient's heart rhythm data. However, added outside physical movement of the patient may cause the defibrillator to collect inaccurate data.
Accordingly, it is desirable to find a solution that allows the delivery of CPR therapy before the administration of a defibrillator shock that does not compromise the safety of the user or patients, or increase the costs or size of the defibrillators. In addition, it is desirable to implement the solution in all types of external defibrillators, including fully automatic, semi-automatic, fully automated or semi-automated and manual defibrillators. Furthermore, other desirable features and characteristics of the invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.